One of the most common and popular tools in use today is the socket wrench. These tools are comprised of a socket driver or handle and a set of sockets of various sizes. Socket drivers are generally available in several different drive sizes, and the sockets are also available in both shallow and deep well types.
A complete tool set can often contain dozens of sockets which are ordinarily stored in socket trays according to their sizes. These trays are unsatisfactory in that the sockets invariably get mixed up and the trays occasionally overturn, with the numerous types and sizes of sockets rolling on the floor in all directions. A second problem is that sockets are identified as to their size only by a small stamped indication on the socket itself. These identifications become difficult to read after the socket has been used for an extended period, and while an experienced mechanic can often identify a socket size by sight, even he will waste a great deal of time by selecting the wrong socket size for a particular job.